A/D converters are a basic building block for the system designer and a myriad of different designs are available. In certain system applications, the analog input signal is subject to unpredictable and significant attenuation. In other applications, the incoming analog signal at a hub location arrives from a number of remote locations via different communication paths. The signal amplitude in these paths experience unwanted amplitude fluctuations which vary in time and from one path to another. Such signal effects can decrease the sensitivity provided by an A/D converter used in these system applications and, in turn, result in substantially degraded system performance. One way of compensating for such effects is to interconnect an automatic gain control device in the analog input signal path to maintain a predetermined signal amplitude. While this arrangement provides satisfactory results, the resulting circuitry can be complex and not amenable to meet the size and cost objectives of certain system applications. Accordingly, an A/D converter which maintains a prescribed sensitivity during the presence of analog signal amplitude fluctuations and which can be provided with digital devices at low cost would be desirable.